You can share a document using the document URL.
Click on 'Share' button at the top right corner of the document.
Set the access control to either "Public" or "Team Name".
Copy the URL, and send it to the person whom you would like to share the document with. They will be able to access the document in the view only mode.
Team Name: Only users in your team can access.
Public: Anyone on the internet who knows the link can access.